The present invention relates to a balloon and more particularly to a balloon with little deflation.
Toy and display balloons have been made of rubber, typically synthetic rubber. Rubber, however, has a porous structure so that the rubber balloon will normally deflate within several days. Such balloons, filled with helium gas instead of air deflate in only one day since helium molecules are much smaller than the oxygen and nitrogen molecules of air.
Polyethylene film and nylon film are also used for balloons. However, there is little difference between the deflation characteristics of polyethylene film and nylon film and those of rubber, in a balloon. In order to prevent the deflation the surface of the polyethylene or nylon film is metalized with aluminum.
It is now common to combine many balloons together to form a decorative display. However, balloons cannot be used in a display for a long period of time unless the problem of deflation is avoided, and while the deflation can be prevented by using aluminum metalized plastic film, prior balloons of this kind have been made up in such a way that a flap-like seam is formed along a weld line where the two sheets of film are welded together. As a result, wrinkles appear on the balloon at the welded portion when the balloon is inflated.
The wrinkles at the balloon body are no problem when the balloon is used as toy, but when combining several balloons together for a display, the wrinkles detract from the appearance. As balloons which are generally spherically shaped are often used for such displays, the wrinkles caused by the aforementioned seams will become a particular problem.